Bump bn.js and node-polyfill-webpack-plugin in /dash/dash-renderer

Bumps [bn.js](https://github.com/indutny/bn.js) to 5.2.3 and updates ancestor dependency [node-polyfill-webpack-plugin](https://github.com/Richienb/node-polyfill-webpack-plugin). These dependencies need to be updated together.


Updates `bn.js` from 4.12.0 to 5.2.3
- [Release notes](https://github.com/indutny/bn.js/releases)
- [Changelog](https://github.com/indutny/bn.js/blob/master/CHANGELOG.md)
- [Commits](indutny/bn.js@v4.12.0...v5.2.3)

Updates `node-polyfill-webpack-plugin` from 2.0.1 to 4.1.0
- [Release notes](https://github.com/Richienb/node-polyfill-webpack-plugin/releases)
- [Commits](Richienb/node-polyfill-webpack-plugin@v2.0.1...v4.1.0)

---
updated-dependencies:
- dependency-name: bn.js
  dependency-version: 5.2.3
  dependency-type: indirect
- dependency-name: node-polyfill-webpack-plugin
  dependency-version: 4.1.0
  dependency-type: direct:production
...

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Author: dependabot[bot]